1. Field of the Invention
The present invention relates to a semiconductor substrate treatment liquid such as a rinsing liquid, a developer, or a stripper, a treatment method therefor, and a method of manufacturing a semiconductor-substrate product using these.
2. Description of the Related Art
A process of manufacturing a semiconductor device includes various processes such as a lithography process, an etching process, and an ion implantation process. The process of manufacturing a semiconductor device typically includes a process of performing a treatment on an organic material after completion of each process or before moving to the next process. For example, a treatment of stripping and removing a resist remaining on a surface of a substrate is carried out (stripping treatment). Alternatively, a treatment of cleaning the surface is occasionally carried out after the removal or stripping (rinsing treatment). Further, it is necessary to precisely remove a resist only at a desired location in a developing process (developing process).
As a conventional method for stripping an organic residue, a process of using a concentrated sulfuric acid hydrogen peroxide mixture (SPM) or an ammonia-peroxide mixture (APM) is used (see JP2005-268308A, JP2005-189660A, and JP2012-049391A). In this manner, a resist after a substrate is processed can be effectively stripped off. Meanwhile, according to this method, since the oxidizability of a treatment liquid is extremely strong even though the release properties of the resist are excellent, materials constituting the substrate may be damaged. When the recent situations of miniaturization of a semiconductor device and advancement of high integration are considered, it is desirable to avoid such damage even if the damage is minute. Further, even from the viewpoint of reliability, the method of using an SPM or an APM is not necessarily satisfactory due to handleability of chemicals and occurrence of a rapid increase in the temperature.
For this reason, a cleaning technique in which there is little influence on a gate insulating film or a substrate and which has excellent reliability is required, and a new treatment method using foaming of carbonic acid gas has been suggested as one of the cleaning techniques (see JP2012-094703A and JP2012-094702A).